3rd Grade Math: Numbers with Decimals

As a 3rd grader, you are probably learning about decimals and fractions for the first time this year. You may find it tricky at first, but decimals and fractions are some of the most useful math tools for everyday life. Keep reading to learn more about decimals.

Find available tutors

Learning Decimals

What Are Decimals?

Decimals represent numerical amounts that are less than one. You may not realize it, but every time you buy an item, you are dealing with decimals. Let's say you buy a piece of candy for 99 cents. You can write 99 cents as a decimal like this: $0.99. Similarly, if you buy a bottle of juice for $2.50, you're still working with decimals because you're paying two whole dollars and then 50 cents ($0.50) of another dollar.

What Are Fractions?

Fractions and decimals give you two different ways of writing the same numbers. For example, 'four-tenths' can be written as 0.4 or 4/10. Similarly, 'eighty-eight hundredths' can be written as 88/100 or .88.

Both fractions and decimals can be understood as part of a whole number. If you have a pizza divided into six slices, and you eat two, you have eaten 2/6 of the pizza. In other words, you have eaten a part of the whole. The fraction 2/6 is the same as 1/3, because you can make three groups of two slices each. You can also write 1/3 in decimal form, as 0.33.

Decimal Addition

Eventually, you will learn how to add numbers with decimal points. Although you likely won't encounter this until 4th grade, you have actually already added and subtracted decimal amounts because you learned to add and subtract money.

The total price for milk and a loaf of bread might be $2.75 + $3.05. To calculate, write the 2.75 over the 3.05. Then, carry the decimal point down so that it is under the addition problem, but still lines up with the decimals in 2.75 and 3.05. Finally, add the numbers. The answer is $5.80.

If one number is whole (like 3 or 20) and the other one is a decimal, you can add them by writing point zero after the whole number. For example, three would become 3.0, and 20 would become 20.0. This makes it easier to line up the decimal points.

You can use a sales receipt for practice adding decimals. Ask your parent for a grocery store receipt. Fold over the bottom of the receipt so you can't see the total. Add the numbers on a separate piece of paper and check your answer by looking at the receipt total when you're done. Below are some sample problems with answers to demonstrate adding with decimals.

Did you find this useful? If so, please let others know!

Other Articles You May Be Interested In

  • More Blog Articles
    Understanding Prime Numbers

    Prime numbers are positive integers that have fascinated people for thousands of years. If your child struggles to grasp prime numbers, it may help to gain a deeper understanding of how they're defined. Your child may also benefit from knowing how to identify them and how they're useful in nature.

  • More Blog Articles
    Obesity Targeted by Task Force in Tennessee Schools

    Numerous studies show the ill effects that being obese or overweight have on health. So if you're near the bottom of the 'most-obese states' list, it's likely time to do something about it. When Tennessee found itself in that spot, it began its fight to shed pounds with the formation of the Tennessee Obesity Task Force. Are the...

We Found 7 Tutors You Might Be Interested In

Huntington Learning

  • What Huntington Learning offers:
  • Online and in-center tutoring
  • One on one tutoring
  • Every Huntington tutor is certified and trained extensively on the most effective teaching methods
In-Center and Online


  • What K12 offers:
  • Online tutoring
  • Has a strong and effective partnership with public and private schools
  • AdvancED-accredited corporation meeting the highest standards of educational management
Online Only

Kaplan Kids

  • What Kaplan Kids offers:
  • Online tutoring
  • Customized learning plans
  • Real-Time Progress Reports track your child's progress
Online Only


  • What Kumon offers:
  • In-center tutoring
  • Individualized programs for your child
  • Helps your child develop the skills and study habits needed to improve their academic performance
In-Center and Online

Sylvan Learning

  • What Sylvan Learning offers:
  • Online and in-center tutoring
  • Sylvan tutors are certified teachers who provide personalized instruction
  • Regular assessment and progress reports
In-Home, In-Center and Online

Tutor Doctor

  • What Tutor Doctor offers:
  • In-Home tutoring
  • One on one attention by the tutor
  • Develops personlized programs by working with your child's existing homework
In-Home Only


  • What TutorVista offers:
  • Online tutoring
  • Student works one-on-one with a professional tutor
  • Using the virtual whiteboard workspace to share problems, solutions and explanations
Online Only

Our Commitment to You

  • Free Help from Teachers

  • Free Learning Materials

  • Helping Disadvantaged Youth